An oil filter assembly for a differential housing, including a filter housing for releasably mounting in a drive axle housing and defining an internal volume for containing oil to be filtered, a mounting arrangement for releasably securing the filter assembly to a drive axle housing, and a filter element for filtering particulate contaminants from oil in a drive axle. The filter housing includes an inlet on an upper portion thereof and an outlet on a lower portion thereof to define an flow path therethrough, and wherein the filter element is located downstream of the inlet.